(i) Differences between innate immunity and acquired immunity are:Innate Immunity: 1.It includes the defence elements with which an individual is born.2.It consists of various types of barriers that prevent the entry of foreign agents.3.It remains throughout life.Acquired Immunity: 1.It is immunity which is acquired after birth.2.It consists of specialised cells (T-cells and B-cells) and antibodies that circulate in the body fluid.3.It can be short lived or life long.(ii) Differences between active immunity and passive immunity are:Active Immunity: 1.It is developed due to contact with pathogen or its antigen.2.It has no side effects.3.It is slow but long lasting.4.It takes time to develop its response.5.e.g. vaccination for polio, etc.Passive Immunity: 1.It is developed when ready-made antibodies are injected into the body.2.It may cause a reaction.3.It is fast but lasts only for few days.4.It is used when the immune response has to be faster.5.e.g. administration of tetanus antitoxins, etc.